1. Field of the Invention
The present invention relates generally to catheters utilizing guidewires, and more particularly, relates to catheters with proximal connectors facilitating the movement of guidewires.
2. Description of the Prior Art
Catheters for insertion into the body have been known in the medical arts for many years. These may be used for diagnostic purposes, such as in various radiology applications, or may be used therapeutically, as in angioplasty and atherectomy procedures. U.S. Pat. No. 4,808,164 issued to Hess describes a multipurpose catheter. U.S. Pat. No. 4,650,466 issued to Luther and U.S. Pat. No. 4,748,984 issued to Patel describe catheters designed for use in atherectomy procedures.
A key feature in the clinical use of a catheter is the ability of the attending physician to steer the distal end of the catheter through the body to the desired diagnostic or treatment site. To accomplish this end, catheter manufacturers have employed a number of techniques. One of the most common approaches is through the use of a guidewire which is often employed in an internal lumen of the catheter. The references discussed above all teach the use of a guidewire with the catheter disclosed.
A number of catheter designs have employed fixed guidewires. The chief advantage of this approach is the steerability afforded by combined and independent rotation of the guidewire and the sealing of the lumen in which the guidewire is located. This also promotes a low profile. The prime disadvantages of the fixed guidewire catheter include inability to adjust the length of the guidewire in relation to the length of the catheter and to remove the guidewire to free the lumen for other purposes. U.S. Pat. No. 4,664,113 issued to Frisbie shows a typical fixed guidewire catheter design.
Because of the disadvantages with fixed guidewire systems, many current catheter systems employ removable guidewires. U.S. Pat. No. 4,748,982 issued to Horzewski, et al. discusses a balloon angioplasty catheter with a totally removable guidewire. However, the guidewire lumen of the Horzewski, et al. device is not sealed.
U.S. Pat. No. 4,646,742 issued to Packard, et al. and U.S. Pat. No. 4,846,174 issued to Willard, et al. also teach catheters with removable guidewires. These devices employ a seal on the proximal end of the catheter for purposes of sealing an internal thru-lumen. These devices, however, fail to provide for the rotation of the guidewire without the attachment of an independent rotation knob to the proximal end of the guidewire.
A major improvement to catheter systems having removable guidewires is the ability to seal the guidewire lumen. U.S. Pat. No. 4,838,269 issued to Robinson shows the use of an O-ring to seal the proximal end of the guidewire lumen. However, the Robinson catheter yet has the key disadvantage of the difficulty in rotation of the guidewire combined with the independence of rotation of the catheter.